Brilliant! Do you know that every time I encountered Mother Hildegarde in the books I pictured Frances de la Tour! She's a brilliant actress and one who just seems perfect for this role.

De la Tour's career spans five decades across theatre, film and television. On the TV side, her many credits include Poirot, Waking The Dead, Marple, New Tricks and BBC One’s Big School. She is also a regular on the ITV sitcom Vicious (pictured), which is currently in the middle of its second season and airs on PBS in the United States.

And on the film side... well I think a lot of us remember her as Madame Maxine in Harry Potter but has recently been in Into the Woods, Hugo, and Alice in Wonderland.

Mother Hidegarde is a key figure in the second book Dragonfly In Amber (which season two is based on), Mother Hildegarde is the intelligent and commanding Mother Superior who runs L’Hopital Des Anges in Paris. A tall, gaunt woman with a deep and powerful voice, Hildegarde comes from an aristocratic, well-connected family.